physical education. n. (Education) training and practice in sports, gymnastics, etc, as in schools and colleges. Abbreviation: PE. physâ²ical educaâ²tion. n. instruction in sports, exercise, and hygiene, esp. as part of a school or college program.
3. Stress/injury. Stress on the tissues or any type of injury in the mouth can cause canker sores. Since the sores are actually tiny ulcers, they can be caused by any kind of hard brushing or eating something that can cause bruises or lead to tissue inflammation in the mouth.
They are caused by herpes virus infection and later crust over with a scab and are usually associated with tingling, tenderness or burning before the actual sores appear on or around the lips. Mouth irritation. The irritation can be caused by: 1  Biting your cheek, tongue or lip. 2  Wearing braces or another type of dental apparatus, or having a sharp broken tooth. 3  Chewing tobacco. 4  Burning one's mouth from hot food or drinks. 5  Having gum disease (gingivitis) or other mouth infection.